Rock drill



c. F. osGooD ROCK DRILL Filed 001'.. '7, l9 41 Dec. 14, 1943.

uw. vw .0.

Q xnxmhww@ mm. \N

Patented Dec. 14, 1943 ROCK DRILL Charles F. Osgood, Claremont, N. H., assignor to Sullivan Machinery Company, a corporation of Massachusetts Application October 7, 1941, Serial No. 414,021

l Claims.

This invention relates to rock drills and more particularly to improvements in a rotation release mechanism for a hammer rock drill.

An object of the present invention is to provide a novel rotation release mechanism. Another object is to provide an improved release mechanism for the rotation means of a hammer rock drill whereby steel rotation may be interrupted without interrupting operation of the drill hammer motor. Another object is to provide an improved rotation release mechanism having novel operating and controlling means. A further object is to provide an improved rotation release mechanism associated with the ratchet and pawl mechanism of the drill steel rotation means whereby the pawls may be released and held from engagement with the ratchet teeth thereby to interrupt drill steel rotation. A still further object is to provide a novel rotation release ring coaxial with the ratchet and pawl mechanism, which is rotatable into a position to release and hold the pawls from engagement with the ratchet teeth. Yet another object is to provide a novel means actuated by pressure fluid for rotating the release ring to effect pawl release, and having novel controlling means associated therewith. Still another object is to provide in a drill steel rotation means having a stationary pawl carrier and a rotatable ratchet ring, a rotatable release ring coaxial with the pawl carrier for releasing the pawls from engagement with the ratchet teeth thereby to release the ratchet ring for free rotation. A further object is to provide a rotation release mechanism which is simple and rugged in construction, and compact in design. With the above and other objects inrview, this invention relates to certain novel features of construction, operation and arrangement of parts, an example of which is given in the specication and illustrated in the accompanying drawing, wherein:

Fig. 1 is a view in longitudinal vertical section through a rock drill in which an illustrative embodiment of the invention is incorporated.

Fig. 2 is an enlarged cross sectional view taken substantially on line 2-2 of Fig. 1.

Fig. 3 is an enlarged cross sectional View taken substantially on line 3-3 of Fig. 1.

Fig. 4 is a sectional view similar to Fig. 3 showing the release ring in rotation releasing position.

Fig. 5 is a perspective view of the release ring.

Fig. 6 is a detail sectional view taken on line 6-6 of Fig. 2.

In this illustrative embodiment of the invention, the improved rotation release mechanism is associated with the drill steel rotation mechanism of a hammer rock drill. The rock drill is herein of conventional design-and embodies a drill hammer motor comprising a motor cylinder I having a bore 2 containing a reciprocatory hammer piston 3. The hammer piston has a forwardly'projecting striking bar 4 for delivering impact blows to the shank of a conventional drill steel 5 carried within a usual rock drill chuck 6. The hammer motor cylinder has a front head l and a rear head 8 and arranged at the rear end of the motor cylinder is a rear head block 9. The rear head block carries a throttle valve mechanism I0 for controlling the flow of pressure fluid from a suitable source of supply through passage means II to a fluid distributing valve mechanism I2.

As is usual in rock drills of the type disclosed, a rotation mechanism operated by the hammer piston is provided for rotating the drill steel as the latter is percussively actuated. This rotation mechanism includes a spirally grooved rifle bar I3 slidingly interlocked with a rifle nut I4 secured Within the hammer piston. Associated with the rifle bar is an intermittent grip mechanism for intermittently holding the rifle bar against rotation in one direction whereby rotary motion is imparted to the hammer piston, preferably during the return stroke of the latter. The rotary motion of the hammer piston is transmitted to the drill steel in the usual manner through straight grooves I5 on the piston striking bar 4 slidingly interlocked with a chuck nut I6 secured to a rotatable chuck sleeve Il of the chuck 6. The intermittent grip mechanism includes a rotatable grip or ratchet ring I8 having internal ratchet teeth I9 and integrally secured to the rifle bar I3. Arranged concentrically within the rotatable ratchet ring is a stationary pawl carrier 20 which carries usual spring-pressed gripping elements or pawls 2I engaging the teeth of the ratchet ring. The pawl carrier 20 has its hub 22 keyed at 23 to a stationary cylindric projection 24 integral with the rear head block 9. The riile bar I3 has a rearward cylindric portion 25 journaled in a bearing sleeve supported Within the stationary pawl carrier. As shown in Fig. 2, the throttle valve mechanism I0 includes a throttle valve 26 received in a transverse bore in the rear head block 9 and having an operating handle 2l. A supply hose connection 28 is adapted to supply pressure fluid through a space 29 to the hollow interior of the throttle valve and the latter is adjustable to control the low of presiting movement of the plunger.

:the throttle valve mechanism riphery. The release ring is guided for rotary movement but is held against endwise movement In this instance, the pawlsA in a suitable manner. 2I are elongated and project outwardly'atA 33 Within the release ring 3 I and -the-cutaway portions or notches 32 on the release ring permit the pawls 2| to move into engagement with the ratchet teeth I8 in a manner shown inlig. 23.'

When the release ring is rotated from lthe prosition in Fig. 3 to that shown in Fig. 4, the release ring at its inner periphery engages the pawls 2l to Hmove the latter from engagement with the ratchet teethand Yto hold the pvawls in released position. The operating means 4for the release ring comprises va fluid actuated plunger 34 having an annular-groove 35 -in -which a lug or vpin 36 secured to the release ring projects as shown in Fig. ,6. The plunger 434 has at one end a piston 31 received in a bore 38 and at its other `erniaa projection 39 engageable with a plug ,40 for lim- Arranged abe tween the plunger and V,the plug 4,0 and encircling the projection 39 is a coil spring ,4,I which coi-1- .stantly vurges the plunger -in one direction, ,Ars ranged in a nlug 4.2 secured to the :rear 4head .block 9 is a plunger valve .43 reciprocablymounted in a bore 44. The stem 45 of this gplunger Valve has a push button .48, .and-a coi-l spring 41 urges the plunge-r valve toward its real'mostfposi.- tion. The valve receiving here 44 is connected by a passage 48 to the pressure :flzuid space 129 ,ef I so that the passage `is is in constant communication with the source of pressure fluid supply. A passage 449 `connects .the valve receiving bore 44 with. :the vbore 3.8 containing the nliinserepiston V31.- jA branch passage .5s connects the passage 49 tutti a vent passage L. `The; piston. valve @i3-.hss spacedannular grooves 52,7153. :and when vthe xga-Ive is in the position shouldn ,1, the passage@ v.communicating with the :p stonrecei-,ving here 3 8 is in communication with the vent passage 51 through the valve groove *5.2.-` j j The mode .of operation `oi the :impnovedrotation release mechanism .is :QILIOill-S'ZV When-the piston valve is movedionwardlv .from the position shown in Fig. l, the valve groove frconneots .the supply passage 4 8 with the passage 49 so that pressure fluid may oiv to the .bore y.3,8 to act on the piston 31. 'I he pressure fluid acting `on the plunger-piston 31 moves r,the plunger axially against pressure of the coil spring 4I, and .through the groove 35 and pin 3,5 the release ring 3 I is `rotated into a position to Adisengage the pays/ls from the ratchet teeth thereby to releaselfhe ratchet ring for free rotation.' When the Yratchet ring is free to rotate, rotation of the drill'steel 5 is interrupted and the hammer 'piston may reciprocate percussively to actuate the drilllpsteel Awhile steel rotation is discontinued-and Aat `this time the rifle bar I3 freely oscillates :back Aand forth as the vhammer piston reciprocates'. -it is again desired to effect drill steel rota-iden, the push button 4:6 isfreleased to permit theipiston valve ,4.3 .to be moved rearwardly :by .the coil ,-f

f --or notches 32 permit engagement of the pawls at that time the fluid supply to the passage 49 is cut off and the passage 49 is connected to atmosphere through the branch passage 50, valve groove 52 and the vent passage 5I. When the pressure uid in the bore 38 is vented to atmosphere, the coil spring 4| moves the plunger 34 axially in the opposite direction thereby to elect :rotation of the .release ring 31| 'back to its initial inoperative/position shown in Fig. 3. VWhen the release ring 3| is released and has assumed the 'position shown in Fig. 3, the cut-away portions 2l with the ratchet teeth.

As a resultof-this invention, an improved drill steel rotation mechanism for a rock drill is provided whereby the drill operator may interrupt drill steel rotation at will in an improved manner. YIt, will further be evident that by the provision of the improved rotary release ring assoiciated With'the ratchet and pawl mechanismand .arranged in the ,manner described, the -pawlstmay be released `fromk engagement with .the ratchet ring in an ,improved manner. lIt will further be evident that the improvedstructure is .compara- .ti-vely simple and rugged, is relatively .compact and may be Vreadily and easily operated. Other .uses and advantages `of theinvention will 'be .clearly apparent to those skilledin .the art.

While there is in this application Specifically described one 'form which .the inventionmay as- .sume in practice, Ait will `be .understoodithat this form rvof the same is shown .for ,purposes of .illustration and that ,the invention may be modified and embodiedrin various other forms without Adeparting lfrom :its spiritor the scope of .the `appended claims.

What Iclaim as newand .desire to secure by Letters Patentis: Y A

Ina rockdrill, rotation mechanism adapted vto effeot rotation of a drill steel comprising an @intermittent grip mechanism, said ,grip mecha,-

4mism including-a carrier element, gripping means :carried by said element .and -a grip ring element with which Ysaid Lgripping means isengageable said :carrier and grip ring elements being 4relatively rotatable, a rifle'vbar connected to one .of said relatively rotatable elements, a rotary release -ri-ng arranged at one end ofY said carrier element and engageable withl sai'dg-ripping means to citerai-, upon rotation thereof release .of said .grippi-.rlgfmeans vfromA said grip'pring element, Yand meansyfor eiiecting rotation of said releasering relatively to saidgrip mechanism.

2.51.11 a rock drill, rotation mechanism adapted to effect rotation of -a drill steel comprising `an ,-rneans for effecting rotation of said release ring relatively to said grinmechanism.Y y 3. In a rock drill, rotation mechanisrnadapted .to'etect rotation Aofa vdrill steel c onipiisingA intermittentfgrip mechanism, Vsaid grip mechanism including a stationary carrier, gripping means carried by said carrier and a rotatable grip ring with which said gripping means is engageable, a rifle bar connected to said rotatable grip ring, a rotary release ring arranged in adiacency to said carrier and engageable with said gripping means to eifect upon rotation thereof release of said gripping means from engagement with said grip ring, and means for effecting rotation of said release ring relatively to said grip mechanism.

4. In a. rock drill, rotation mechanism adapted to effect rotation of a drill steel comprising intermittent grip mechanism, said grip mechanism including a stationary carrier, gripping means carried by said carrier and a rotatable grip ring with which said gripping means is engageable, said gripping means having a portion projecting outwardly beyond one end of said carrier and grip ring, a rotary release ring arranged at one end of said carrier and engageable with the projecting portion of said gripping means to eect upon rotation thereof release of said gripping means from engagement with said grip ring,

and means for eifecting rotation of said release ring relatively to said grip mechanism.

5. In a rock drill, rotation mechanism adapted to effect rotation of a drill steel comprising intermittent grip mechanism, said grip mechanism including a stationary carrier, gripping means carried by said carrier and a rotatable grip ring with which said gripping means is engageable, a rie bar connected to said rotatable grip ring, a rotary release ring arranged in adjacency to said carrier and engageable with said gripping means to effect upon rotation thereof release of said gripping means from engagement with said grip ring, means for eifecting rotation of 'said release ring relatively to said grip mechanism, said release ring having a notch at its inner periphery for permitting movement of said gripping means into engagement with said grip ring when said release ring is in inoperative position.

6. In a rock drill, rotation mechanism adapted to eiect rotation of a drill steel comprising intermittent grip mechanism, said grip mechanism including a stationary carrier, gripping means carried by said carrier and a rotatable grip ring with which said gripping means is engageable, said gripping means having a portion projecting outwardly beyond one end of said carrier and grip ring, a rotary release ring arranged at one end of said carrier and engageable with the projecting portion of said gripping means to effect upon rotation thereof release of said gripping means from engagement with said grip ring, means for effecting rotation of said release ring relatively to said grip mechanism, said release ring having a notch at its inner periphery Within Which said projecting portion is received for permitting movement of said gripping means into engagement with said grip ring when said release ring is in inoperative position.

7. In a rock drill, drill steel rotation mechanism including intermittent grip mechanism, said grip mechanism having gripping means, and means for interrupting operation of said grip mechanism including a rotatable release ring arranged in coaxial relation with said grip mechanism and rotatable into engagement With said gripping means to render the latter inoperative, and means for eifecting rotation of said release ring relative to said grip mechanism.

8. In a rock drill, drill steel rotation mechanism including intermittent grip mechanism, said grip mechanism having gripping means, and means for interrupting operation of said grip mechanism including a rotatable release ring arranged in coaxial relation With said grip mechanism and rotatable into engagement with said gripping means to render the latter inoperative, and means for eifecting rotation of said release ring relative to said grip mechanism, said rotation effecting means including a fluid actuated plunger engageable with said release ring.

9. In a rock drill, drill steel rotation mechanism including intermittent grip mechanism, said grip mechanism having gripping means, and means for interrupting operation of said grip mechanism including a rotatable release ring arranged in coaxial relation with said grip mechanism and rotatable into engagement With said gripping means to render the latter inoperative, and means for eifecting rotation of said release ring relative to said grip mechanism, said rotation eifecting means including a fluid actuated plunger engageable with said release ring, said plunger having an annular peripheral groove and said release ring having an operating pin projecting Within said groove.

10. In a rock drill, rotation means for a drill steel comprising ratchet and pawl mechanism, said ratchet and pawl mechanism including relatively rotatable pawl carrier and ratchet elements, said carrier element carrying pawls movable into and out of engagement with said ratchet element, and means for interrupting drill steel rotation at the Will of the operator including rotary release means coaxial with said ratchet and paWl mechanism and engageable With the paWls for moving the same upon rotation of said release means out of engagement with the ratchet element, and means for effecting rotation of said release means relative to said ratchet and paWl mechanism, said release means including a rotary release ring and said rotation effecting means including a plunger for rotating said release ring.

CHARLES F. OSGOOD. 

